Measures taken to respond to the pressures from the introduction of non-indigenous species
In terms of responses, preventing the introduction of non-indigenous species (NIS) is currently considered the only feasible management option for the marine environment. This is a result of the limited practical and cost‐effective means available for eradicating or controlling established NIS in the marine environment. OSPAR has taken action towards reducing the introduction of NIS from ships’ ballast water by developing general guidance on voluntary ballast water exchange as well as establishing a joint task group with HELCOM for the management of NIS in relation to ballast water management exemptions and the management of ballast water and biofouling (JTG BALLAST & Biofouling) This has resulted in the adoption of a joint harmonised procedure for the management of ship’s ballast water and sediments (Agreement 2020-01) by both OSPAR and HELCOM.
NEAES 2030 Operational Objective S7.O2 states that “by 2025 OSPAR will develop a coordinated management approach to ensure the number of non-indigenous species introduced by human activity is minimised and where possible reduced to zero”. To achieve this objective there are opportunities for OSPAR to consider developing measures, including by sharing best practice with respect to the inclusion of marine NIS in national biosecurity plans and by considering the role of emerging vectors for NIS such as offshore renewables or restoration.
The section development has been supported by the collation of relevant measures: measures of relevance to benthic habitats included in this section
This section describes the responses that have been implemented to address non-indigenous species (NIS) within the North-East Atlantic. These responses include the development of policy, legislation and measures to manage or regulate specific human activities or to mitigate impacts on ecosystem services.
The section considers NIS across all Regions of the OSPAR Maritime Area, in coastal, shelf and deep seas within and outside national jurisdiction. The primary focus is on responses that have been adopted by the OSPAR Commission for implementing the Contracting Parties’ commitments under the OSPAR Convention and the strategic objectives of the North-East Atlantic Environment Strategy. Article 22 of the OSPAR Convention requires that the Contracting Parties report to the OSPAR Commission at regular intervals on the steps they have taken to implement OSPAR Decisions and Recommendations, the effectiveness of these measures and the problems encountered in their implementation. This section aims to describe the progress made in implementing these measures and to assess whether they are working in terms of achieving the ambitions set out in the North-East Atlantic Environment Strategy 2030. The section attempts to set OSPAR’s responses in the wider policy context and looks at responses by other competent organizations, where these are pertinent to addressing NIS in the context of the North-East Atlantic.
There are limited practical and cost‐effective means available for eradicating or controlling NIS in the marine environment once these are established. The most feasible and efficient measures are those aimed at preventing the introduction of NIS in the first place, for example through biosecurity or pathway management, awareness raising and education. Monitoring is also a crucial aid to early detection, and thus rapid response and containment.
NEAES 2030 sets out the ambition for OSPAR’s response to addressing NIS under Strategic Objective 7, “Ensure that uses of the marine environment are sustainable, through the integrated management of current and emerging human activities, including addressing their cumulative impacts”, and specifically under Strategic Objective S7.O2, which states that by 2025 OSPAR “will develop a coordinated management approach to ensure the number of non-indigenous species introduced via human activity is minimised and where possible reduced to zero.”
There are a number of linkages to other thematic assessments, including:
The reader is referred to the following feeder reports for additional information on some of the key human activities affecting NIS:
Measures adopted by OSPAR
This section focuses on the measures adopted by OSPAR to control NIS in the North-East Atlantic, including where NIS are considered as a pressure on the OSPAR listed species and habitats.
The implementation status of all OSPAR measures was reported on in 2021.
Addressing species and habitats in decline and under threat
The OSPAR List of threatened and/or declining species and habitats (Agreement 2008-06) was first adopted in 2003 and updated in 2008 and 2021. The List guides the OSPAR Commission in setting priorities for its further work to conserve and protect marine biodiversity in implementing Annex V to the OSPAR Convention. The purpose of the Recommendations adopted by OSPAR to further the protection and conservation of OSPAR listed species and habitats is to achieve agreement on the actions to be taken nationally and collectively to strengthen the protection of the listed species and habitats, recover their status and ensure that they are effectively conserved in the OSPAR Maritime Area. A ‘Common Understanding’ of the Recommendations was adopted in 2013 (Agreement 2013-13). The recommendations are broad in nature, addressing a range of human activities and pressures. Four of the OSPAR Recommendations for the protection and conservation of threatened and/or declining species and habitats specify actions relating to NIS: Recommendation 2020-01 on Ostrea edulis in Region II and III and Ostrea edulis beds in Region II, III and IV, Recommendation 2016-03 on Atlantic salmon in Regions I, II, III and IV, Recommendation 2020-01 on European sturgeon in Regions II, III and IV, Recommendation 2013-01 on littoral chalk communities in Region II.
The most recent implementation reporting took place in 2019, with the next reporting due in 2025. A detailed overview of the scope and range of actions implemented in this reporting round can be found in the .
reports that the introduction and further distribution of NIS is one aspect that still poses a significant threat to native oyster beds. In the process of implementing recommended actions for the flat oyster, Norway raised awareness of the invasive Pacific oyster and the measures being undertaken to address this issue.
One of the collective actions from the Recommendation for littoral chalk communities was to “Monitor key pressures including loss and change of substratum, levels of eutrophication, removal of species, introduction and spread of non‐indigenous species and physical damage". However, according to the 2019 reporting there had not yet been any progress made with this action, and the overview assessment states that its implementation needs to be reconsidered, as it is only addressed through the regular cycle of assessments.
For the European sturgeon, at least two Contracting Parties refer to measures to regulate or prohibit non-native sturgeon. While the species is considered extinct in the UK, with the exception of occasional migrants, the keeping of non-native sturgeon is regulated in order to reduce the risk of such populations becoming established in the wild. Spain prohibits the introduction of non-indigenous sturgeon species. indicates that the introduction of non-native sturgeon into open water remains a pressure on this species in the Greater North Sea, Celtic Seas and the Bay of Biscay and Iberian Peninsula.
Next to aquaculture escapees, the greatest threat to wild Atlantic salmon is the freshwater parasitic lice, Gyrodactylus salaris. Although native to some parts of the Baltic, it does not naturally occur in the Atlantic distribution of Atlantic salmon populations (Johnsen, 2006, OSPAR 2010a). Gyrodactylus salaris is a freshwater parasite which has spread mainly through anthropogenic movement of infected fish between hatcheries/fish farms/rivers and by migration of infected fish from rivers and brackish water in fjords to rivers in Norway, Sweden and Russia. In Norway, catastrophic losses of Atlantic salmon were seen following the introduction of G. salaris to the country in the 1970s. Measures are in place to restrict movements of live fish and eggs and baitfish. In Norway there is also a concern that sea lice may be a carrier and vector of several fish diseases, including new pathogens such as microsporidium (NASCO, 2009).
Monitoring for the parasite and strict control of the movement of stocks between rivers has been an integral part of the Norwegian strategy to prevent the spread of G. salaris. Monitoring programmes to demonstrate freedom from G. salaris are being planned or executed by an increasing number of countries. These programmes can be complicated by difficulties in identifying Gyrodactylus specimens to species level.
Combatting this parasite will be a high priority, the aim being to eradicate the parasite where possible and minimize the risk of transmission to new areas. Measures will be based on the best available technology and systematic follow-up.
At regional scale, numbers of invasive species in littoral chalk communities are noted in the supporting OSPAR background document as being limited. Similarly, the brown alga Sargassum muticum has been reported as present on numerous coastal sites in Upper Normandy but does not give rise to massive exclusions of indigenous species (OSPAR, 2010b). The crab Hemigrapsus saguineus is increasingly common among rock slides and boulders on the upper beach, probably as a result of dispersal from the port of Le Havre. The recommendation calls for collective action to monitor the introduction and spread of NIS with respect to this habitat. To date this has not been implemented.
Are these measures working?:
This assessment indicates that while rates of NIS introduction are declining overall, NIS remains a pressure for certain species and habitats of concern in the North-East Atlantic, which implies that the measures taken to date are not yet having the desired outcome.
Marine Protected Area Network
Within OSPAR, MPAs are understood as areas for which protective, conservation, restorative or precautionary measures have been instituted for the purpose of protecting and conserving species, habitats, ecosystems or ecological processes of the marine environment (as defined in Recommendation 2003-03 implementing Annex V of the OSPAR Convention).
There are unfortunately very few datasets documenting the effect of MPAs on invasive species, and in particular to determine whether MPAs can increase resilience to biological invasions (Giakoumi et al., 2017). The few existing studies have shown contrasting effects (either positive or negative or non-significant) on NIS, except that NIS density is usually greater outside than inside MPAs (Giakoumi et al., 2017). MPAs are generally not a response for addressing the spread or establishment of NIS. However, there may be potentially important management actions that can be taken within protected areas, such as the protection of seabird nesting grounds through predator eradication programmes, or measures to manage some NIS pathways within protected areas to reduce the risk of introduction and spread of other NIS.
Other OSPAR measures responding to relevant human activities and pressures
Transport - Shipping
Prior to the entry into force of the International Convention for the Control and Management of Ships’ Ballast Water and Sediments, 2004 (BWM Convention - see section 3 below), OSPAR adopted an agreement providing general guidance on voluntary interim application of the D-1 ballast water exchange standard by vessels operating between the Mediterranean Sea and the North-East Atlantic and/or the Baltic Sea (OSPAR Agreement 2010-07) and guidance on intra North Sea Ballast Water Exchange Areas (OSPAR Agreement 2014-11). The aim of these agreements was to reduce the introduction of NIS from ballast water in the period up to the full entry into force of the BWM Convention.
One of the other principal responses undertaken by OSPAR to address NIS has been through the “Joint HELCOM/OSPAR Harmonized Procedure for the Contracting Parties of OSPAR and HELCOM on the granting of exemptions under the International Convention for the Control and Management of Ship’s Ballast Water and Sediments, Regulation A-4” (JHP). This is based on the Guidelines for Risk Assessment under Regulation A-4 of the Ballast Water Management (BWM) Convention (G7) (IMO Resolution MEPC.289(71) and was originally agreed by HELCOM and OSPAR Contracting Parties in 2013 (OSPAR Agreement 2020-01). The JHP procedure aims to ensure that exemptions are granted in a consistent manner that does not impair or damage the environment, human health, property or resources. The main users of this procedure include ship owners/operators, port State administrations and relevant experts and researchers. Based on Regulation A-4 of the Ballast Water Management Convention, exemptions from ballast water management requirements described in the JHP can be issued to a ship on voyages between specified ports or locations for a maximum of five years. A port State may grant such an exemption if the risk is acceptably low, based on the results of a risk assessment. In the initial transitional period of the BWM Convention (2017-2024), the JHP is to be implemented in a flexible and practicable way in order to gain experience and to enable further development and improvements.
OSPAR and HELCOM have established a joint task group for the management of NIS in relation to ballast water management exemptions, and the management of ballast water and biofouling (JTG BALLAST & Biofouling). The group’s work includes the development of a system for managing information about priority species of NIS and their occurrence in the region, to be used as a basis for decision making, for example when considering whether an exchange of ballast water by a ship between two port areas gives rise to particular concern.
Are these measures working?:
The measure has supported a consistent approach to the implementation of the BWM Convention. In 2014, OSPAR endorsed the decision to designate ballast water exchange areas in the North Sea. These ballast water exchange areas are intended for intra-North Sea traffic only and the regulation is only temporary. The measure will cease when ships meet regulation D-2 of the BWM Convention.
In 2020 Denmark and Sweden established a bilateral agreement to implement BWC Regulation A-4 and create a ‘Same Risk Area’ designation for the Öresund.
Other relevant activities
The Bow-tie analysis identified a number of other human activities and pressures that could have relevance to NIS, but for which OSPAR has not taken any specific measures; these include hunting and collecting, input of other forms of energy (including electromagnetic fields, light and heat), industrial uses, waste treatment and disposal, marine litter, Aquaculture Feeder Report (§6.5), coastal protection infrastructure, port expansion, extraction of minerals, extraction of oil and gas and non-renewable energy generation (production of energy).
There are potential future opportunities for OSPAR to develop measures with respect to tourism and leisure infrastructure and activities, and renewable energy generation.
Other important measures
This section highlights measures taken by other competent bodies which complement OSPAR’s response for addressing NIS within the North-East Atlantic.
Invasive alien species have been identified as one of the key causes of loss of native species and harm to biodiversity (IPBES, 2019; Diaz et al., 2019). Article 8(h) of the Convention on Biological Diversity (CBD) provides a high-level framework for responses with specific objectives and at different geographic scales. According to this article, Parties to the CBD must, as far as possible and as appropriate, “prevent the introduction of, control or eradicate those alien species which threaten ecosystems, habitats or species”. Decision VI/23 of COP 6 under the CBD, on “Alien species that threaten ecosystems, habitats and species”, sets out in its Annex the Guiding Principles for the prevention, introduction and mitigation of impacts of such alien species and urges Parties to develop national action plans. Concerning the marine environment, the Decision refers to the IMO Ballast Water Convention and calls on Parties to implement it (see also under “Transport - Shipping”).
Within the context of the European Union, efforts under the Marine Framework Strategy Directive (EU/56/2008) are focused on limiting the environmental pressure from NIS by reducing the rate of their introduction and spread through the management of the pathways that they use. Descriptor 2 states that “NIS introduced as a result of human activities are at levels that do not adversely alter the ecosystem”. A similar approach to managing NIS pathways is taken by EU Regulation 1143/2014 on the prevention and management of the introduction and spread of invasive alien species. This measure is a response to Article 8(h) of the CBD and requires Member States to establish a surveillance system for early detection of Invasive Alien Species (IAS) of Union concern. It was not possible to evaluate the national plans that have been developed to determine the extent to which marine and coastal IAS have been taken into account; however, the 2018 reporting in relation to the MSFD stated that Good Environmental Status with regard to NIS would be achieved only after 2020, there being only limited examples of sub-regions or specific locations where D-2 had been achieved. It was also stated that new introductions are under-reported, owing to continuing challenges with consistency in the understanding of terms, data availability and comparability (Tsiamis et al., 2021)
The EU Water Framework Directive (2000/60/EC) does not specifically mention NIS but considers it to be a human pressure that could impact the quality of a water body.
The Arctic Invasive Alien Species (ARIAS) Strategy and Action Plan, produced by Conservation of Arctic Flora and Fauna (CAFF) and the Protection of the Arctic Marine Environment (PAME), sets out the priority actions that the Arctic Council and its partners are encouraged to take to protect the Arctic region from the adverse impacts of invasive alien species or NIS, including in marine ecosystems. The actions take environmental, cultural, and economic perspectives into consideration, including drivers, impacts, and response measures. The actions again focus on the prevention of new introductions as the effort that can bring the largest return on investment. As part of ARIAS implementation, a joint CAFF-PAME project is underway for 2021-2023.
Transport – Shipping is a significant vector for NIS to enter the marine environment in the OSPAR area and primarily transfers marine NIS in two ways: the exchange of ballast water or through organisms transported on ships’ hulls (biofouling).
The International Convention for the Control and Management of Ships’ Ballast Water and Sediments, 2004 (BWM Convention) is a global response for preventing the effects of the spread of invasive species carried by ships’ ballast water and sediments, which entered into force globally on 8 September 2017. This is a crucial step towards reducing the spread of NIS regionally and worldwide. The BWM Convention requires ships in international traffic to apply ballast water management measures, such as ballast water exchange (D-1), or to fulfil a certain discharge standard (D-2). The latter requires the installation of a certified ballast water treatment device which sterilizes the ballast water and thus prevents it from transferring species. Existing ships must initially meet the D-1 standard, but by 2024, all must meet the D-2 standard. Every ship is required to have a Ballast Water Management Plan and International Ballast Water Management Certificate, and to keep a Ballast Water Record Book. The IMO has also issued guidelines on aspects of implementation and continues to review the operation of the Convention during the current experience-building phase. Several amendments to the Convention and the Code for Approval of Ballast Water Management Systems (BWMS Code), which replaces the former G8 Guidelines, came into force in October 2019; amendments and revised guidance were also adopted in 2020. As of 15 September 2020, 88 States and IMO Associate Members had ratified the Convention (IMO, 2020), including all OSPAR Contracting Parties other than the United Kingdom, although the latter is drafting legislation and operates in accordance with the Convention’s guidelines.
A Risk Assessment approach is applied for the granting of exemptions from ballast water management requirements, and guidelines have been adopted to ensure that the provisions of regulation A-4 of the BWM Convention are applied in a consistent manner and based on scientifically robust risk assessment. This ensures that the general and specific obligations of a Party to the Convention are achieved (Resolution MEPC.289(71)). In the case of the North-East Atlantic and the Baltic Sea, this is delivered through the Joint OSPAR/ HELCOM procedure (see section 2.3 above).
For biofouling, IMO adopted the Guidelines for the control and management of ships' biofouling to minimize the transfer of invasive aquatic species (Biofouling Guidelines) (IMO resolution MEPC.207(62) in 2011. These guidelines are intended to provide a globally consistent approach to the management of biofouling, which is the accumulation of various aquatic organisms on ships’ hulls. The guidelines have been supplemented by two guidance documents:
- in 2012, the Guidance for minimizing the transfer of invasive aquatic species as biofouling (hull fouling) for recreational craft (MEP.1/Circ.792); and
- in 2013, the Guidance for evaluating the 2011 guidelines for the control and management of ships' biofouling to minimise the transfer of invasive aquatic species (MEPC.1/Circ.811).
At its seventy-second session in April 2018, the MEPC agreed to a new output enabling the Sub-Committee on Pollution Prevention and Response (PPR) to review the Biofouling Guidelines, which will be based on the principles of the 2013 Guidance. The Glofouling project was established in 2018 for five years, to help build capacity for the implementation of the guidelines https://www.glofouling.imo.org/.
Globally, a proposal submitted to the IMO Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP) highlighted that the application of the IMO Biofouling Guidelines had been inconsistent and mentioned challenges such as dealing with irregular surfaces and cavities and assessing the efficacy of new in-water cleaning technologies (GESAMP, 2019). The International Council for the Exploration of the Sea ( ICES) has also highlighted improvements that could be made such as targeted guidelines dependent on vessel type and operational profiles, hull form optimisation, and better assessment of compliance (Galil et al., 2019).
Aquaculture - marine, including infrastructure
At the EU level, Council Regulation (EC) No 708/2007, concerning the use of alien and locally absent species in aquaculture, aims to optimise the benefits associated with introductions and translocations while at the same time avoiding alterations to ecosystems, preventing negative biological interaction - including genetic change - with indigenous populations, and restricting the spread of non-target species and detrimental impacts on natural habitats. This response does not apply to the Pacific oyster, which is identified as a species of concern in relation to the OSPAR- listed flat oyster.
The majority of the responses identified are measures taken in respect of coastal and shelf areas rather than the open ocean and deep seas, reflecting the focus of human activities and the highest risk for introduction pathways – particularly in the Greater North Sea, Celtic Seas and Bay of Biscay and Iberian Coast. The Contracting Parties of the Arctic region are also delivering the Arctic Invasive Alien Species (ARIAS) Strategy and Action Plan under the Arctic Council. The sharing of information and approaches could help to ensure consistency in the approaches adopted across this region of the OSPAR Maritime Area.
Gaps and opportunities
Are we doing enough?:
The latest OSPAR Indicator Assessment on Trends in New Records of NIS shows an overall reduction in the rate of NIS introduction, which indicates that reduced pressure (a decreasing NIS trend) has generally been achieved in the assessed regions of the Greater North Sea, Celtic Seas and Bay of Biscay and Iberian Coast. This trend is, however, associated with great uncertainty. Thus, while the rate of new NIS introduction is high, the indication of a decreasing trend towards the most recent assessment period might suggest that the current measures are having the effect of reducing the introduction and spread of NIS in the OSPAR Maritime Area. Since the 2010 QSR, there has been significant progress in the responses to address NIS. However, introductions continue, and this issue will require continued effort to prevent further introductions. Continued implementation of the joint response by OSPAR and HELCOM, the MSFD, the Invasive Alien Species Regulation and the IMO Ballast Water Management Convention should ensure that some of the identified gaps in monitoring are addressed and also strengthen standardised monitoring so as to reduce bias and data gaps. Some vectors of introduction and spread could also be better targeted. For instance, while (commercial) shipping has been well targeted (see above), management of leisure boating is still in the early stages. There are national examples such as the Recreational Boating Pathway Action Plan of the GB Non-native Species Secretariat (2020).
Climate change-induced change in marine environmental conditions is anticipated to affect the introduction and spread of NIS, but more climate modelling is required to quantify this risk. Consideration of such developments will need to be a part of the response development and adaptation process.
Are there other types of responses that could be undertaken by OSPAR to improve the status of benthic habitats?
NEAES 2030 Operational Objective S7.O2 states that by 2025, OSPAR “will develop a coordinated management approach to ensure the number of non-indigenous species introduced by human activity is minimised, and where possible reduced to zero.” As a contribution to this objective, OSPAR may wish to consider the following opportunities for additional responses.
Strengthening national biosecurity plans:
In the framework of CBD Decision VI/23 and its Europe-wide implementation through EU Regulation 1143/2014, countries are required to develop national action plans. Understanding the extent to which these national biosecurity action plans are being used as a management tool within the OSPAR Maritime Area could help contribute to the 2030 objectives.
Restoration and NIS:
OSPAR has committed to contribute to achieving the ambitions of the CBD Post-2020 Global Biodiversity Framework, which has established a target for the restoration of ecosystems, including marine ecosystems, as well as the aims of the UN Decade for Ecosystem Restoration. This commitment is articulated in the 2030 NEAES, which contains a specific strategic objective to restore degraded ecosystems and four operational objectives relating to clean seas, biologically diverse and healthy seas and seas resilient to climate change and ocean acidification (Strategic Objective 6), in particular S6.O1. By 2023, OSPAR aims to identify habitats suitable for restoration and develop a common knowledge base on the most appropriate and effective methods for restoration of degraded habitats. There is an opportunity to continue to develop best practice in restoration while also avoiding the potential introduction or spread of NIS through these initiatives, for example by building on current guidance such as the European Guidelines on Biosecurity in Native Oyster Restoration (zu Ermgassen et al., 2020).
Offshore renewables as stepping stones for NIS:
Construction for the purposes of offshore renewable energy production is considered to have a positive benefit on biodiversity (in terms of species richness) in soft-bottomed habitats, by providing hard substrate on which organisms can settle. However, there is also potential for these submerged structures to act as stepping- stones for the spread of NIS, and / or to expand their distributional range and facilitate their spread (Langhamer, 2012). The ICES advice covers potential impacts on marine life, including benthos, fish, birds, and marine mammals. In the case of benthos, most changes would be local and site-specific, with broader spatial effects mainly associated with tidal barriers or lagoons. Benefits for the benthic habitat can be achieved through infrastructural design or the exclusion of bottom fishing. However, colonisation of structures by non-indigenous species could also occur.
It is suggested that the 2008 OSPAR guidance on environmental considerations for the development of offshore wind farms (Agreement 2008-03) should be used as part of the licensing procedure for offshore developments. Currently, this guidance does not address NIS and how to reduce the opportunity for renewable structures to facilitate their spread. There is perhaps an opportunity to update this guidance, for example by including consideration of the types of construction materials to be used. OSPAR has established an intersessional correspondence group on renewable developments (ICG-ORED) which will contribute to delivery of the OSPAR NEAES 2030 Strategic Objectives and operational objective S7.O2. This new ICG presents an opportunity to consider possible measures relating to windfarm development as a vector for NIS spread.
Recreational boating and NIS:
Recreational boating activities can also be responsible for the introduction of NIS. In the case of the Didemnum vexillum – a high-impact, globally-invasive sea squirt – McKenzie et al. (2017) consider recreational boating to be a high-risk vector for primary introduction and secondary spread of non-native ascidians. Within OSPAR, the Netherlands, France, Ireland, the United Kingdom and Spain are affected, and specimens are also found on the west coast of Norway.
In general, such biofouling species create a range of complications. They are considered one of the primary issues affecting the marine aquaculture industry, can outgrow and out-compete other species, and might also disturb the spawning of the Atlantic herring (McKenzie, et al., 2017).
Another important gap in our knowledge of the responses needed to reduce NIS spread concerns climate change and human settlements. The ICES highlights that the disappearance of summer Arctic Sea ice as a consequence of climate change may lead to an increased invasion of the Arctic by non-native species, owing to more extensive human development (Ruiz and Hewitt, 2009).
Currently, OSPAR does not directly address the recreation and tourism sector in its work. However, it does address various pressures which can be associated with this sector. Through its Regional Action Plan on Marine Litter, OSPAR is taking various measures to reduce marine litter in the North-East Atlantic. Furthermore, OSPAR addresses issues like eutrophication, hazardous substances, biological diversity and the protection of species and habitats. To reduce the pressures and impacts from the recreation and tourism sector, OSPAR might also address them via these other existing working areas.
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